1. Field of the Invention
The present invention relates to a mirror box, which is mounted in an electronic still camera, to lead light entering through a photographing lens selectively to a view-finder or an imaging device such as a CCD.
2. Description of the Related Art
Conventionally, there is known an electronic still camera which is a single-lens reflex type. The single-lens reflex camera is provided with a quick return mirror, which is set on an optical path between the photographing lens and the imaging device, to lead the incident light from the photographing lens the view-finder. Conversely, in a photographing operation, the quick return mirror is retracted from the optical path, so that a subject image is formed on the imaging device.
In an electronic still camera which utilizes a CCD as the imaging device, an optical low-pass filter removing a high-frequency component is fixed between the photographing lens and the CCD, so as to prevent the generation of moiré fringes. Moiré fringes occur when the incident light has a high-frequency component, so that the image quality is lowered. similarly, an infrared cut filter may be provided for preventing the deterioration of exact color reproduction, which occurs because of infrared light.